Sole support for use with ski bindings

ABSTRACT

A safety device is disclosed for supporting the sole of a skier&#39;&#39;s boot on a ski generally adjacent a ski binding which is adapted to release the ski boot when the ski boot is subjected to a predetermined force, the safety device facilitating low friction movement and release of the ski boot relative to the ski when subjected to the predetermined force.

United States Patent Asp 14 Sept. 24, 1974 54] SOLE SUPPORT FOR USE WITH SKI 3,511,516 5/1970 Smolka et al. 280/1135 c BINDINGS 3,689,094 9/1972 Marker et al. 280/1135 C [76] Inventor: Gerald H. Asp, 135 S. Lasalle St.,

l-linsdale, 111. 60603 [22] Filed: Nov. 5, 1973 [21] App]. No.: 412,952

[52] US. Cl 280/1l.35 C

[51] Int. Cl. A63c 9/08 [58] Field of Search 280/1135 C, 11.35 R, 28111 1 2X 1 3 w [5 6] References Cited UNITED STATES PATENTS 3,446,511 5/1969 Marker 280/1135 C 3,448,990 6/1969 Cubberley et al 280/1135 C Primary Examiner-David Schonberg Assistant ExaminerDavid M. Mitchell Attorney, Agent, or FirmFitch, Even, Tabin & Luedeka [5 7] ABSTRACT A safety device is disclosed for supporting the sole of a skiers boot on a ski generally adjacent a ski binding which is adapted to release the ski boot when the ski boot is subjected to a predetermined force, the safety device facilitating low friction movement and release of the ski boot relative to the ski when subjected to the predetermined force.

13 Claims, 3 Drawing Figures SOLE SUPPORT FOR USE WITH SKI BINDINGS The present invention relates generally to skiing, and more particularly to a safety device for use in supporting the sole of a skiers boot on a ski generally adjacent a releasable ski binding to facilitate low friction movement and release of the ski boot from the ski.

The rise in popularity of skiing as a sport has emphasized the need for safety bindings which adequately retain the skiers boots in proper position on his skis but allow release of the skiers boots from the skis when subjected to forces which would cause injury, as during a severe fall, if the skier were not released. Advances in safety binding design have introduced the concept of toe and heel bindings which include elements adapted to pivot relative to the surface of the ski such that when the ski boot is subjected to a predetermined force acting generally laterally or obliquely to the axis of the ski, the toe or heel binding will pivot to release the boot from the ski. Such release of either of the skiers boots is necessary to allow rotation of the legs relative to the skis during a fall wherein one or both of the skis is prevented from rotating while the skiers body may roll or rotate relative to his skis in a manner as to increase the probability of a spiral fracture or other break in the leg bones if the associated ski boot isnot released from the ski.

Recent advances in ski safety bindings have also introduced safety devices employed to support the sole of the ski boot on the ski in a manner to reduce friction between the boot sole and the ski and thereby facilitate movement and release of the ski boot from the ski when subjected to a predetermined force acting generally laterally or obliquely to the longitudinal axis of the ski. The present invention is directed to the latter type of safety device and in particular provides an improved safety device for supporting the sole of a ski boot on a ski generally adjacent a releasable ski binding to facilitate low friction movement of the ski boot in a release direction when subjected to an abnormal force acting generally laterally or obliquely to the axis of the ski.

The terms generally laterally and generally obliquely, as employed herein to describe the forces acting between a ski boot and its associated ski in a direction which may effect release of the ski boot from its associated ski bindings, are intended to cover the full directional range of forces that may act on the ski boot and cause release thereof. Conventionally, relative forces between a ski boot and a ski which act in a direction parallel to the longitudinal axis of the ski will not effect release of the ski boot from the ski bindings. However, the present invention facilitates low friction movement of the ski boot in substantially any direction relative to the associated ski, considered in a plane generally parallel to the upper surface of the ski, so that the present invention is not dependent upon the particular type of safety release bindings employed to retain the ski boot on the ski.

One of the primary objects of the present invention is to provide a safety device for use in supporting the sole of a ski boot on a ski, which device greatly reduces frictional resistance to movement of the ski boot relative to the ski in a direction to release the boot from the ski when either the ski or the ski boot is subjected to a force acting generally laterally or obliquely to the longitudinal axis of the ski.

Another object of the present invention is to provide, a safety device for use in supporting the sole of a skiers boot on a ski in a manner to facilitate release movement of the skiers boot relative to the ski, which device includes means operative under a first coefficient of friction to facilitate a first movement of the ski boot relative to the ski in a direction to release the ski boot, and means operative under a second coefficient of friction to facilitate a second continued movement of the ski boot relative to the ski in the direction to release the ski boot, with the first coefficient of frictionbeing lower than the second coefficient of friction.

Another object of the present invention is to provide a safety device as described having an outer elastomeric element secured to a pedestal which is adapted for attachment to a ski, and an intermediate element which slidingly cooperates with the elastomeric cover element and the pedestal to facilitate movement of the cover element and intermediate element relative to the pedestal under the first coefficient of friction, the elastomeric cover element being thereafter further movable relative to the intermediate element under the second coefficient of friction to facilitate further movement of the ski boot relative to the ski when subjected to a predetermined force acting generally laterally or obliquely to the axis of the ski.

A feature of the present invention lies in the provision of a totally enclosed chamber wherein is disposed the intermediate element and a lubricant material in a manner to prevent the entry of movement inhibiting contaminants or the like between the relatively movable surface areas.

A further feature of the present invention lies in the provision of a safety device which facilitates movement of a ski boot in substantially any direction in a plane generally parallel to the surface of the ski when the ski boot is subjected to a force tending to release the boot from the associated safety bindings.

Yet another feature of the present invention lies in the provision of a safety device which facilitates movement of the ski boot relative to the ski and which is selfcentering so as to be normally returned to a neutral position upon release of the ski boot from the device.

Further objects and advantages of the present invention, together with the organization and manner of operation thereof, will become apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawing wherein like reference numerals designate like elements throughout the several views, and wherein:

FIG. 1 is a top plan view of a safety device in accordance with the present invention mounted on the upper surface of a ski generally adjacent a releasable toe binding to underlie the sole of a skiers boot, the toe binding and ski boot being partially illustrated in phantom;

FIG. 2 is an enlarged plan view of the safety device shown in FIG. 1, portions being broken away to better illustrate the various elements of the device; and

FIG. 3 is an enlarged vertical sectional view taken substantially along the line 3-3 of FIG. 1, looking in the direction of the arrows.

Referring now to the drawings, and in particular to FIG. 1, a safety device constructed in accordance with the present invention is indicated generally at 10. The safety device 10 finds particular application in supporting the sole of a skiers boot, indicated in phantom at 12, on a ski 14. The safety device is illustrated and described herein as supporting the area of the sole of the ski boot 12 underlying the ball of the skiers foot. However, it will be understood that a similar safety device 10 may also be mounted on the ski 14 to support the heel area of the ski boot 12. The safety device 10 is illustrated in FIG. 1 as being mounted on the ski 14 generally adjacent and rearwardly of a safety toe binding indicated in phantom at 16. The ski 14 is of the conventional downhill type and has the toe binding 16 mounted thereon in a conventional manner for engagement with the toe of the skiers boot sole 12. The toe binding 16 is preferably of the type normally termed a safety binding and is adapted to release the toe of the ski boot sole 12 when the ski boot is subjected to a predetermined force acting generally laterally or obliquely of the longitudinal axis of the ski 14. Such forces often occur when the skier falls and his body and one or both of his legs rotate as he rolls while his skis are substantially prevented from rotation due to engagement with the snow surface while retained on his ski boots. The ski binding 16 is theoretically adjusted to release the associated skiers boot when a force is established between the skiers boot and the ski which would cause injury to the skier unless his boot is released from the ski; thus, a safety binding.

As noted, the safety device 10 is illustrated as being positioned so as to underlie the ball of the skiers boot when his ski boot is secured onto the ski 14. The safety device 10 facilitates movement of the skiers boot with respect to the ski during safety release of the boot from the ski by providing low friction resistance to movement of the ski boot relative to the ski in a direction which would cause release of the ski boot from the as sociated ski bindings. The safety device 10 thus serves as a friction-reducing means which facilitates safety release of the skiers boot from the ski and assists in the effective operation and purpose of safety bindings. For example, it will be appreciated that when the weight of a skier is transferred forwardly onto his skis during a fall, the frictional forces tending to prevent movement of the skiers boots relative to his skis would normally substantially increase. The safety device 10 prevents such increased resistance to movement of the ski boot relative to its associated ski by maintaining a low friction movable surface which is engaged by the sole of the ski boot. Additionally, the safety device 10 prevents any accumulation of ice and/or snow or other foreign matter between the ski boot sole and the upper surface of the ski from inhibiting movement of the ski boot in a direction to release the ski boot from its bindings during a safety release.

With reference to FIG. 1, taken in conjunction with FIGS. 2 and 3, the safety device 10 includes pedestal means, indicated generally at 18, which includes a generally planar mounting plate 20 and an upstanding pedestal 22. The mounting plate 20 may have any plane configuration and is preferably made of a suitable metallic material. The mounting plate 20 is adapted to be secured to the upper surface of the ski 14 and, to this end, the illustrated mounting plate has three mounting holes 24 therethrough to receive mounting screws 26 for securing the mounting plate onto the ski 14. It will be understood that other suitable means may be employed to secure the mounting plate 20 onto the ski l4.

The pedestal 22 may be made of a suitable metallic or high strength plastic material and is fixedly mounted onto the mounting plate 20. If desired, the pedestal 22 may be made of the same metallic material as the mounting plate 20 and may be formed integral therewith. In the illustrated embodiment, the pedestal 22 is made separately from the mounting plate 20 and is received within a circular opening 27 in the mounting plate to which the pedestal is affixed as by staking at'a lower edge 29 of the pedestal or by other suitable means. In the illustrated embodiment, the pedestal 22 is generally circular, when considered in plan configuration, and has an upper planar surface 28 which is disposed parallel to the plane of the upper surface of the ski 14 when the pedestal and associated mounting plate 20 are secured onto the ski. A low friction surface 30 is provided on the upper surface of the pedestal 22 and may comprise a relatively thin sheet of polytetrafluoroethylene plastic material, a sheet of combined fiberglass and polytetrafluoroethylene material bonded to the upper surface 28 of the pedestal, a spray coating of polytetrafluoroethylene applied directly onto the pedestal, or other low friction material.

The safety device 10 includes an outer elastomeric cover element, indicated generally at 32, which is mounted on the pedestal means 18 and is adapted for engagement with the lower surface of the ski boot sole 12. The pedestal 22 includes an annular depending wall portion 34 which defines an annular groove 36 about the pedestal to receive an upstanding annular rim or bead 38 formed integral with the cover element 32 so as to fixedly retain the cover element on the pedestal means 18. The cover element 32 is formed of a suitable elastomeric material capable of maintaining its elastomeric characteristics throughout a temperature range as might be encountered during skiing, such as above approximately F. down to approximately 50F. The cover element 32 has a lower wall portion 40, which has the annular bead 38 formed thereon, an annular generally vertically disposed wall portion 42 and an upper horizontal wall portion 44 which overlies the pedestal 22. When mounted on the pedestal means 18, the cover element 32 defines a totally enclosed chamber between the cover element and the pedestal means 18.

The upper horizontal wall 44 of the cover element 32 is provided with a fabric reinforced central section 46 which provides a relatively high wear resistant and puncture resistant surface for engagement with the lower surface of the ski boot sole 12. The wall thickness of the cover element 32 is selected so as to resist collapse under its own weight and normally maintain the cross sectional configuration as illustrated in FIG. 3.

A lower surface 47 of the upper wall 14 of the cover element 32 is provided with a plurality of downwardly projecting concentric annular rings or beads 48 formed integral with the wall 44. In the illustrated embodiment, five such concentric beads 48 are formed on the lower surface 47 of the cover element 44 and each has a mean diameter approximately 0.400 inch larger than the diameter of the next smaller bead. Each bead 48 i has a semicircular cross section having a radius of approximately 0.006 inch with the center of the radius lying in the plane of the lower surface 47.

The chamber defined between the cover element 32 and the pedestal means 18 receives an intermediate element, indicated generally at 50, formed from a low coefficient of friction material. Desirably, the intermediate element 50 has limited flexibility and may be formed of a disc shaped member made from a high or ultrahigh molecular weight polyethylene material having high impact strength, such as polyethylene, nylon, Delrin or the like. The intermediate member 50 has a generally flat central wall portion 52 and a depending annular wall portion 54 formed integral with the central wall portion 52. The intermediate element 50 has a circular plan configuration such that the outer annular surface of the depending wall 54 is disposed in close proximity to the inner surface of the annular wall 42 of the cover element 32. When positioned within the chamber defined between the cover element 32 and the pedestal means 18, the depending wall portion 54 of the intermediate element 50 depends downwardly below the plane of the upper surface 28 of the pedestal 22 such that lateral movement of the intermediate element 50 relative to the pedestal 22 is limited by engagement of the depending annular wall 54 with the depending annular wall 34 of the pedestal.

By forming the intermediate element 50 with a plan configuration generally corresponding in size and shape to the inner diameter of the annular wall 42 of the cover element 32, the intermediate element 50 and cover element 32 cooperate to provide a self-centering bias of the cover element 32 relative to the pedestal 22 of the pedestal means 18. For example, if the ski boot sole 12 is moved relative to the ski 14 while in engagement with the cover element 32, the intermediate element 50 will be caused to move relative to the pedestal 22 a distance limited by engagement of the depending annular wall 54 with the annular wall 34 of the pedestal 22. When the ski boot 12 no longer engages the upper surface 46 of the cover element 32, the intermediate element 50 and elastomeric cover element 32 are returned to a neutral generally centered position relative to the pedestal 22, as shown in FIG. 3, due to the elastic properties of the cover element cooperating with the more rigid properties of the intermediate element 50.

A lubricant, indicated at 58, is disposed within the enclosed chamber defined between the cover element 32 and the pedestal means 18. The lubricant 58 totally surrounds the intermediate element 50 so as to be disposed betweeri the central flat wall portion 52 and the upper surface of the polytetrafiuoroethylene sheet 30 on the pedestal 22, and between the central portion 52 and the lower inner surface of the upper wall 44 of the cover element 32. The lubricant 58 may be selected from any of the well-known lubricants which are compatible with the materials of the pedestal 22, the low friction sheet 30 and the cover element 32, and which have viscosity characteristics such that they retain their lubricity at temperatures normally encountered in snow skiing which may vary between about 70F. down to 50F. Commercially available generally constant viscosity silicone greases or oils may be employed for this purpose.

The intermediate element 50 is provided with a plurality of openings 60 in the flat wall portion 52 which serve as reservoirs for the lubricant 58. In the illustrated embodiment, five reservoir openings 60 are provided in the element 50, four of which are equidistantly circumferentially spaced on a common diameter about a center opening 60.

In operation, when the skiers boot is attached to the ski 14 by means of the releasable toe binding 16 and a rearwardly disposed releasable heel binding (not shown) with the ball of the skier's foot overlying the safety device 10, the weight of the skier will press the upper wall 44 of the cover element 32 downwardly such that the concentric beads 48 engage the upper surface of the central portion 52 of the intermediate element which, in turn, is pressed downwardly against the upper low friction surface 30 disposed on the pedestal 22. It will be understood that a relatively thin film of the lubricant 58 is maintained between the intermediate element 50 and the upper wall 44 of the cover element 32 and between the intermediate element and the sheet 30 on the pedestal 22 during the full range of operation of the safety device 10. By making the intermediate element 50 of a properly chosen plastic material, a relatively low coefficient of friction is established between the intermediate element 50 and the lower friction surface 30 on the pedestal 22. The coefficient of friction established between the intermediate element 50 and the lower surface 47 of the upper wall 44 of the cover element 32 will be slightly greater than the coefficient of friction between the intermediate element and the surface 30 on the pedestal 22.

When a force is created between the ski boot l2 and the ski 14 which is of sufficient magnitude and acts in a direction to initiate movement of the toe binding 16 in a direction to release the ski boot sole 12, the force acting through the ski-boot sole 12 will cause the cover element 32 and intermediate element 50 of the safety device 10 to slide over the upper sheet 30 on the pedestal 22 in the direction of the applied force. The intermediate element 50 undergoes low friction lateral sliding movement relative to the pedestal 22 until the depending annular wall 54 thereon engages the depending wall 34 of the pedestal 22 whereupon further sliding movement of the intermediate element 50 relative to the pedestal 22 is prevented. Thereafter, the elastomeric and flexibility characteristics of the cover element 32 allow the cover element to continue a lateral movement in the direction of the applied force in sliding relation on the upper surface of the intermediate element 50 until the sole 12 of the ski boot is released by the safety toe binding 16. After release of the ski boot sole 12 from the safety device 10, the intermediate element 50 and upper cover element 32 return to neutral self-centered positions as illustrated in FIG. 3.

It can be seen that by providing the intermediate element 50in the safety device 10 in accordance with the present invention, a first relatively low coefficient of friction is created between the intermediate element and the upper sheet 30 on the pedestal 22 which provides only slight resistance to initial lateral movement of the intermediate member. This substantially reduced friction between the intermediate element 50 and the pedestal means 18 allows low friction displacement of the ski boot sole 12 relative to the ski 14 when aforce is created between the ski boot and the ski 14 tending to move the ski boot relative to the ski. When the ski boot sole 12 has undergone movement sufficient to move the intermediate element 50 to its limit of sliding relative to the pedestal 22, the ski boot sole will undergo continued movement under low-friction resistance due to sliding movement of the upper wall 44 of the cover element 32 on the upper surface of the intermediate element 50.

Thus, a substantially reduced frictional resistance to movement of the ski boot relative to the ski 12 is afforded by the safety device 10 of the present invention. The provision of two sliding surface conditions, i.e., the intermediate element 50 on the upper surface 30 of the pedestal 22 and the upper wall 44 of the cover element 32 on the upper surface of the intermediate element 50, serves to provide substantially reduced resistance to movement of the ski boot sole 12 in a direction to allow release from the associated ski binding. This feature, coupled with the ability of the intermediate element 50 to cooperate with the cover element 32 and effect a self-centering movement of the cover element after disengagement with the ski boot sole l2 affords a substantially improved safety device over the known safety devices of this general type. The safety device 10 affords low friction movement of the associated ski boot in any direction, although the movement will generally be lateral or oblique relative to the axis of the ski 14 due to restrictions in movement of the ski boot imposed by the ski bindings. Some forward movement of the ski boot on the ski is afforded by most ski bindings, as during a forward fall, and the safety device 10 facilitates this movement as well. Additionally, the plan configurations of the pedestal 22, the cover element 32, and the intermediate element 50 may vary from the described circular configurations without hindering operation of the safety device 10.

While a preferred embodiment of the present invention has been illustrated and described, it will be obvious to those skilled in the art that changes and modifications may be made therein without departing from the invention in its broader aspects. Various features of the invention are defined in the following claims.

What is claimed is:

1. A safety device for use in supporting the sole of a skiers boot on a ski and facilitating movement of the skiers boot relative to the ski, said device comprising pedestal means adapted to be secured to the upper surface of the ski, an elastomeric element adapted for engagement with the sole of the ski boot and being secured to said pedestal means in generally overlying relation thereto to define therewith a totally enclosed chamber therebetween, and an intermediate element disposed within said chamber and adapted for limited sliding movement on said pedestal means under a first coefficient of friction therebetween when the ski boot is initially subjected to a force tending to move it relative to the ski, said elastomeric element being slidable with said intermediate element until the movement of said intermediate element is limited relative to said pedestal means whereafter said elastomeric element is adapted to undergo further sliding movement relative to said intermediate element under a second coefficient of friction therebetween as the ski boot is subjected to said force tending to move it relative to said ski.

2. A safety device as defined in claim 1 wherein said pedestal means includes an upper planar surface, and wherein said intermediate element comprises a generally flat disc-like element having a lower surface slidable with said planar surface of said pedestal means and an upper surface presented for sliding engagement with said elastomeric element, said intermediate element having a peripheral configuration similar to the inner peripheral surface of said elastomeric element but of a size greater than said planar surface of said pedestal means such that said intermediate element and said outer elastomeric element may be moved simultaneously relative to said pedestal means.

3. A safety device as defined in claim 1 including a lubricating material disposed within said enclosed chamber so as to be disposed between said intermediate element and said pedestal means and between said intermediate element and said outer elastomeric element.

4. A safety device as defined in claim 1 wherein the outer peripheral configuration of said intermediate element is substantially similar in size to the inner peripheral surface of said elastomeric element so as to cooperate therewith to effect self-centering of said cover element and intermediate element relative to the pedestal means after release of the ski boot from said safety device.

5. A safety device as defined in claim 1 wherein said pedestal means includes a continuous peripheral wall portion, and wherein said intermediate element comprises a disc-like member having a peripheral depending wall adapted to engage said peripheral wall of said pedestal means when said intermediate member has been moved a predetermined distance relative to said pedestal means.

6. A safety device as defined in claim 1 wherein said elastomeric element has'a generally planar upper surface at least a portion of which is reinforced with a wear resistant non-elastomeric material for engage ment with the sole of a skiers boot.

7. A safety device as defined in claim 1 wherein said intermediate element is made of a relatively high molecular weight polyethylene material having a generally planar surface adapted for sliding relation with said pedestal means, and wherein said pedestal means includes a polytetrafluoroethylene surface disposed for engagement with said intermediate member.

8. A safety device as defined in claim 3 wherein said intermediate element includes at least one lubricant reservoir opening therein.

9. A safety device as defined in claim 1 wherein said elastomeric element has a plurality of generally concentric annular beads formed thereon in opposed relation to said intermediate element.

10. A safety device for use in supporting the sole of a skiers boot on a ski generally adjacent a ski binding adapted to selectively release the boot upon relative selective movement between the boot and the ski, said device comprising, pedestal means adapted to be secured to the upper surface of a ski and having a generally planar upper surface disposed parallel to the surface of the ski when mounted thereon, a sole engageable elastomeric element secured to said pedestal means in overlying relation thereto and defining therewith a totally enclosed chamber therebetween, an intermediate element disposed within said chamber and having a first surface slidable on said planar surface of said pedestal means under a first coefficient of friction therebetween, said intermediate element having a second surface slidably engageable with the opposing surface of said elastomeric element under a second coefficient of friction therebetween greater than said coefficient of friction between said intermediate element and said pedestal means, said intermediate element having means thereon to limit the extent of movement thereof relative to said pedestal means, said intermediate element and said elastomeric element being simultaneously movable relative to said pedestal means until said intermediate element reaches its limit of movement with respect to said pedestal means whereafter said elastomeric element may move a further distance relative to said intermediate element, said elastomeric element and said intermediate element being cooperative to effect return thereof to centered positions relative to said pedestal means after release of the skiers boot therefrom.

11. A safety device as defined in claim including a lubricant disposed within said enclosed chamber and interposed between said intermediate element and said pedestal means and between said intennediate element and said opposing surface of said elastomeric element.

12. In a ski assembly having a toe binding adapted to retain the toe of a ski boot in relatively fixed position onto a ski but adapted to release the toe of the ski boot when subjected to a predetermined force, the combination therewith of a safety device for supporting the sole of a ski boot and facilitating movement of the ski boot when subjected to said predetermined force, said safety device comprising pedestal means adapted to be secured to the ski and having a generally planar surface disposed parallel to the upper surface of the ski when said pedestal means is mounted thereon, an outer elastomeric element adapted for engagement with the sole of the ski boot and being secured to said pedestal means in generally overlying relation thereto to define a chamber therebetween, and an intermediate element disposed within said chamber and adapted for limited sliding movement on said pedestal means under a first coefficient of friction therebetween when the ski boot is initially subjected to a force tending to move it with respect to the ski, said elastomeric element being slidable with said intermediate element until the movement of said intermediate element is limited relative to said pedestal means whereafter said elastomeric element is adapted to undergo further sliding movement on said intermediate element under a second coefficient of friction as said ski boot is continually subjected to the force tending to move it relative to said ski.

13. The combination of claim 12 including a lubricant disposed within said chamber and surrounding said intermediate element. 

1. A safety device for use in supporting the sole of a skier''s boot on a ski and facilitating movement of the skier''s boot relative to the ski, said deviCe comprising pedestal means adapted to be secured to the upper surface of the ski, an elastomeric element adapted for engagement with the sole of the ski boot and being secured to said pedestal means in generally overlying relation thereto to define therewith a totally enclosed chamber therebetween, and an intermediate element disposed within said chamber and adapted for limited sliding movement on said pedestal means under a first coefficient of friction therebetween when the ski boot is initially subjected to a force tending to move it relative to the ski, said elastomeric element being slidable with said intermediate element until the movement of said intermediate element is limited relative to said pedestal means whereafter said elastomeric element is adapted to undergo further sliding movement relative to said intermediate element under a second coefficient of friction therebetween as the ski boot is subjected to said force tending to move it relative to said ski.
 2. A safety device as defined in claim 1 wherein said pedestal means includes an upper planar surface, and wherein said intermediate element comprises a generally flat disc-like element having a lower surface slidable with said planar surface of said pedestal means and an upper surface presented for sliding engagement with said elastomeric element, said intermediate element having a peripheral configuration similar to the inner peripheral surface of said elastomeric element but of a size greater than said planar surface of said pedestal means such that said intermediate element and said outer elastomeric element may be moved simultaneously relative to said pedestal means.
 3. A safety device as defined in claim 1 including a lubricating material disposed within said enclosed chamber so as to be disposed between said intermediate element and said pedestal means and between said intermediate element and said outer elastomeric element.
 4. A safety device as defined in claim 1 wherein the outer peripheral configuration of said intermediate element is substantially similar in size to the inner peripheral surface of said elastomeric element so as to cooperate therewith to effect self-centering of said cover element and intermediate element relative to the pedestal means after release of the ski boot from said safety device.
 5. A safety device as defined in claim 1 wherein said pedestal means includes a continuous peripheral wall portion, and wherein said intermediate element comprises a disc-like member having a peripheral depending wall adapted to engage said peripheral wall of said pedestal means when said intermediate member has been moved a predetermined distance relative to said pedestal means.
 6. A safety device as defined in claim 1 wherein said elastomeric element has a generally planar upper surface at least a portion of which is reinforced with a wear resistant non-elastomeric material for engagement with the sole of a skier''s boot.
 7. A safety device as defined in claim 1 wherein said intermediate element is made of a relatively high molecular weight polyethylene material having a generally planar surface adapted for sliding relation with said pedestal means, and wherein said pedestal means includes a polytetrafluoroethylene surface disposed for engagement with said intermediate member.
 8. A safety device as defined in claim 3 wherein said intermediate element includes at least one lubricant reservoir opening therein.
 9. A safety device as defined in claim 1 wherein said elastomeric element has a plurality of generally concentric annular beads formed thereon in opposed relation to said intermediate element.
 10. A safety device for use in supporting the sole of a skier''s boot on a ski generally adjacent a ski binding adapted to selectively release the boot upon relative selective movement between the boot and the ski, said device comprising, pedestal means adapted to be secured to the upper surface of a ski and having a generally planar upper surface disposed parallel to the Surface of the ski when mounted thereon, a sole engageable elastomeric element secured to said pedestal means in overlying relation thereto and defining therewith a totally enclosed chamber therebetween, an intermediate element disposed within said chamber and having a first surface slidable on said planar surface of said pedestal means under a first coefficient of friction therebetween, said intermediate element having a second surface slidably engageable with the opposing surface of said elastomeric element under a second coefficient of friction therebetween greater than said coefficient of friction between said intermediate element and said pedestal means, said intermediate element having means thereon to limit the extent of movement thereof relative to said pedestal means, said intermediate element and said elastomeric element being simultaneously movable relative to said pedestal means until said intermediate element reaches its limit of movement with respect to said pedestal means whereafter said elastomeric element may move a further distance relative to said intermediate element, said elastomeric element and said intermediate element being cooperative to effect return thereof to centered positions relative to said pedestal means after release of the skier''s boot therefrom.
 11. A safety device as defined in claim 10 including a lubricant disposed within said enclosed chamber and interposed between said intermediate element and said pedestal means and between said intermediate element and said opposing surface of said elastomeric element.
 12. In a ski assembly having a toe binding adapted to retain the toe of a ski boot in relatively fixed position onto a ski but adapted to release the toe of the ski boot when subjected to a predetermined force, the combination therewith of a safety device for supporting the sole of a ski boot and facilitating movement of the ski boot when subjected to said predetermined force, said safety device comprising pedestal means adapted to be secured to the ski and having a generally planar surface disposed parallel to the upper surface of the ski when said pedestal means is mounted thereon, an outer elastomeric element adapted for engagement with the sole of the ski boot and being secured to said pedestal means in generally overlying relation thereto to define a chamber therebetween, and an intermediate element disposed within said chamber and adapted for limited sliding movement on said pedestal means under a first coefficient of friction therebetween when the ski boot is initially subjected to a force tending to move it with respect to the ski, said elastomeric element being slidable with said intermediate element until the movement of said intermediate element is limited relative to said pedestal means whereafter said elastomeric element is adapted to undergo further sliding movement on said intermediate element under a second coefficient of friction as said ski boot is continually subjected to the force tending to move it relative to said ski.
 13. The combination of claim 12 including a lubricant disposed within said chamber and surrounding said intermediate element. 